Health Insurance Coverage

Figure 1

Click the link to access our Shiny App on Uninsured Rates in the United States from 2008-2015.

Figure 2A

The following figure displays the trend in the uninsured rate between 2008 and 2015. Results are shown for the USA average (in black), as well as for every individual state (in color). The states are group by Bureau of Economic Analysis (BEA) regions - this allows us to analyze regional trends, and also to identify a state by filtering down to its respective region on this interactive plot.

We see a clear downward trend in the uninsured rate once most of the Affordable Care Act (ACA) provisions were implemented in 2014. The overall US uninsured rate decreased from 18.2% in 2010 to 10.5% in 2015.

However, note that the disparities in uninsured rates largely continue to persist among the states, with regional patterns. States of the Southeast and Southwest consistently had the highest uninsured rates, while states of New England consistenely had the lowest insured or highest health insurance coverage rates.

Figure 2B

The following plot provides a visual depiction of the narrowing in dispersal of the states’ uninsured rates over the period of 2008 to 2015. It can be seen that by 2015, there is a concentration of states’ uninsured rates especially within the range of 7.5% to 12.5%.

Figure 3

In the following plot, we explore the difference between Democratic and Republican states, based on the 2012 US Presidential Election results. Generally, the democratic states consistently have had largely have a lower uninsured rate than the Republican states, though both groups experienced declines in the uninsured rates in 2014. The rate of decline of uninsured rates in 2014 for some Republican states appeared to exceed that of the Democratic states, mainly because of their higher starting point.

Figure 4

We also know that the Medicaid expansion was found to be a big driver of the fall in uninsured rates (accounting for more than half of the decrease). Hypothesizing that this was highly correlated to party affiliation, we made the following bar graph. It confirmed our suspicions that Democratic states were more likely to opt for Medicaid expansion, whereas Republican states were more likely to opt out. This could be a possible explanation for the continued lower insured rates in Democratic states after 2014.

Figure 5

We want to provide a clearer comparison across of the gains in insurance coverage due to the ACA. Thus, we plotted the decrease in uninsured rate (or equivalently, the increase in insured rate) for the states from 2010 to 2015. We find that it is the West Coast states of Oregon, Nevada and California that led in gains in insurance coverage. Republican states are not all ranked at the bottom, and many of them are in the middle of the pack (again due to their higher starting point).

Figure 6A

This plot shows insured rates in 2015 at a glance, looking at how they differ by party (2012 winner), BEA region and income level of the states.

In terms of correlations, it appears that being a Democratic state is a strong predictor of a higher insurance rate. States in New England, the Mideast and the Great Lakes perform well in insurance rates, while states in the Southwest, Rocky Mountains and Southeast perform the poorest. As expected, high-income states have the highest insurance rates as more people would be able to afford insurance. Lower and lower-middle income states have lower coverage rates, but it is infact the lower-middle income states that have the lowest insurance rates.

Figure 6B

We now make these same categorizations, but looking at the gains in insurance coverage between 2010 and 2015. We notice that Republican states at actually have higher gains in insurance rate than Democratic states (although Democratic states have a higher 3rd quartile). The Far West, Southwest and Southeast make the greatest gains in insurance coverage, but still had the lowest insured rates in 2015. The lower the income of the state, the greater the gains in insurance coverage although they still end up with the lowest insurance rates in 2015.

Figures 6A and 6B together suggest that the trends by party, region and income have been preserved from 2010 to 2015, but the gap between the high-performing groups and the low-performing groups has narrowed.

Figure 7

Next, we investigate the main health insurance and coverage sources, namely employer coverage, the individual marketplace, Medicaid / Childrens’ Health Insurance Program (CHIP), and Medicare for the aged. We broke down the results by party and income level, taking a simple (unweighted) average across the states in the categories. We observe that employer coverage rates increase as income level increases, especially for Democratic states. Democratic and low income states have more people on Medicaid / CHIP than Republican and low income states.